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Plate X. — Ceratodon purpureas 



(i) Plant, XI. (2) Leaf, X44- (3) Leaf, X44 (4) Leaf-tip, X125. (5) Cells 

 of leaf-middle, X400. (6) Cells of leaf-base, X400. (7) Capsule; g, goitre, Xi8. 

 (8) A split tooth of the peristome, X125. 



(i) Leaf, I, 



Plate XL — Ceratodon conicus 

 X(2) Leaf-tip, X125. (3) Capsule; g, goitre, X18, 



5. DiTRiCHUM (Leptotrichum) 



Stem usually short, sparingly branched. Leaves not 2-ranked, lanceolate 

 or subulate, entire or serrulate. Cells at leaf-base rectangular, not enlarged 

 in basal angles; tip cells mostly narrow. Calyptra cucullate. Seta slender, 

 erect, twisted. Capsule erect, ovoid or cylindric; lid conic to rostrate; teeth 16, 

 split nearly to base, slender, nodose, smooth or papillose. Spores small. — (Gk. 

 di = 2; thrix = hair; because the teeth of the peristome are commonly split 

 into 2 hair-like parts.) 



la. Leaves 3-7 mm. long, only the shorter remaining 3 mm. 



